The invention relates to an extended
tension leg platform on the basis of oblique upright columns. The extended
tension leg platform comprises a rectangular annular pontoon
assembly. The rectangular annular pontoon
assembly comprises four pontoons, and four upright columns are respectively connected to the upper surfaces of four intersections of the pontoon
assembly in a fastened manner; a part of each upright column is positioned below a water surface, and other parts of each upright column are positioned above the water surface; the part, which is positioned below the water surface, of each upright column is of a vertical structure, and the parts, which are positioned above the water surface, of each upright column are oblique towards the center of the pontoon assembly; an included
angle alpha is formed between the center line of the bottom of each upright column and the horizontal center line of the pontoon assembly; each upright column outwardly extends relative to the pontoon assembly, a plurality of tension leg suspension points are arranged on the outer side of the
tail end of each extending upright column, a tension leg is suspended on each tension leg suspension point, and the
tail end of each tension leg is connected onto a
seabed mud surface in a fastened manner; a
deck which is used for accommodating
oil production equipment, oil and gas treatment equipment and
well drilling and repairing equipment is connected to the tops of the upright columns in a fastened manner.